MANDOCERR_DT_NOTITLE
mandoc_msg(MANDOCERR_DT_NOTITLE, nb->line, nb->pos, "TH");
mandoc_msg(MANDOCERR_DT_NOTITLE, 0, 0, "EOF");
mandoc_msg(MANDOCERR_DT_NOTITLE, n->line, n->pos, "Dt");